/interpreter/tags/at2-build060407/src/edu/vub/at/actors/net/cmd/CMDProvideService.java

 1/**
 2 * AmbientTalk/2 Project
 3 * CMDProvideService.java created on 22-feb-2007 at 20:24:31
 4 * (c) Programming Technology Lab, 2006 - 2007
 5 * Authors: Tom Van Cutsem & Stijn Mostinckx
 6 * 
 7 * Permission is hereby granted, free of charge, to any person
 8 * obtaining a copy of this software and associated documentation
 9 * files (the "Software"), to deal in the Software without
10 * restriction, including without limitation the rights to use,
11 * copy, modify, merge, publish, distribute, sublicense, and/or
12 * sell copies of the Software, and to permit persons to whom the
13 * Software is furnished to do so, subject to the following
14 * conditions:
15 *
16 * The above copyright notice and this permission notice shall be
17 * included in all copies or substantial portions of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
20 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
21 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
22 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
23 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
24 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
25 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
26 * OTHER DEALINGS IN THE SOFTWARE.
27 */
28package edu.vub.at.actors.net.cmd;
29
30import edu.vub.at.actors.natives.ELVirtualMachine;
31import edu.vub.at.actors.natives.Packet;
32import edu.vub.at.actors.net.comm.Address;
33import edu.vub.at.actors.net.comm.CommunicationBus;
34
35/**
36 * A CMDProvideService message is sent asynchronously to all connected VMs when
37 * an actor on the sender VM provided a new publication. Connected VMs are notified
38 * of this such that they can match this new publication with local subscriptions. 
39 * 
40 * SENDER: the VM that provides a new publication
41 * RECEIVER: all connected VMs
42 * MODE: ASYNCHRONOUS, MULTICAST
43 * PROPERTIES: the subscription info: topic and provided service object
44 * REPLY: none
45 * 
46 * @author tvcutsem
47 */
48public class CMDProvideService extends VMCommand {
49
50	private final Packet serializedTopic_;
51	private final Packet serializedService_;
52	
53	public CMDProvideService(Packet topic, Packet service) {
54		super("provideService");
55		serializedTopic_ = topic;
56		serializedService_ = service;
57	}
58	
59	public void send(CommunicationBus dispatcher) {
60		dispatcher.sendAsyncMulticast(this);
61	}
62	
63	/**
64	 * When a remote VM receives the notification, it checks whether any local subscriptions
65	 * can be matched with the new published service.
66	 */
67	public void uponReceiptBy(ELVirtualMachine remoteHost, Address senderAddress) {
68		// notify local discovery actor of the new provided service
69		remoteHost.discoveryActor_.event_remotePublication(serializedTopic_, serializedService_);
70	}
71	
72}